We are interested in locating genes precisely on chromosomal DNA for a variety of human skin diseases which are under study by our laboratory group. DNA may be obtained from a variety of sources including peripheral blood leukocytes, and from cells exfoliated from buccal mucosa. Tiny amounts of material can be expanded using current technology in order to derive a great amount of genetic information from a single sample. We have enrolled 62 patients with epidermolysis bullosa (EB) and 64 unaffected relatives in this study to date.